Cars, trucks, boats, trains, and planes often include frames with hollow cavities. Hollow cavities are often created in these products to reduce overall weight of the product, as well as to reduce material costs. However, introducing hollow cavities into a frame may reduce the overall strength of the frame, and may also increase noise and vibration in other parts of the vehicle.
To alleviate these, as well as other negative effects, hollow cavities often include reinforcements, including various expandable materials. Such reinforcements can decrease noise and vibration while increasing the structural stiffness of the product, thereby allowing for significant weight and material cost reductions. Some current reinforcement systems include expandable foam applied to a rigid carrier. The foam expands during the manufacturing process, securing the rigid carrier in place as the foam contacts the walls of the hollow cavity.
Reinforcement systems can provide additional structural reinforcement, as well as other benefits, through the use of novel shapes, materials, and configurations.